Rover Cracks Mystery Of Mars Spheres

From: UFO UpDates - Toronto <ufoupdates.nul>
Date: Fri, 19 Mar 2004 14:22:50 -0500
Fwd Date: Fri, 19 Mar 2004 14:22:50 -0500
Subject: Rover Cracks Mystery Of Mars Spheres
Source: CNN.Com
http://edition.cnn.com/2004/TECH/space/03/18/mars.blueberries/index.html
Friday, March 19, 2004 Posted: 1438 GMT
Rover Cracks Mystery Of Mars Spheres
By Leonard David
SPACE.com
(SPACE.com) - Scientists have learned the composition of the
mysterious sphere-shaped objects scattered across the crater
floor at Meridiani Planum, the landing site of the Opportunity
Mars rover.
By using a Mossbauer Spectrometer mounted on Opportunity's robot
arm, a patch of the tiny spherules - also called "blueberries",
although they are not blue - received close examination and
have now been identified as hematite.
The spectrometer is designed to study minerals that contain
iron, which are common on the martian surface. Also used to pin
down the makeup of the spherules was the rover's Mini-Thermal
Emission Spectrometer, a scientific instrument that can
recognize minerals formed in water. Meridiani: shallow lake?
This new evidence further supports the hypothesis that the
hematite mineral was likely formed in a former standing body of
water. The Meridiani area, it is thought, was once a shallow
lake.
Once Opportunity wheels itself out of its current shallow crater
site, scientists expect the hematite-rich spherules to litter
the landscape at Meridiani Planum.
Philip Christensen, a Mars Exploration Rover scientist from
Arizona State University in Tempe, announced the finding this
week at the 35th annual Lunar and Planetary Science Conference
being held in Houston, Texas. Formation via precipitation
"This finding further supports the hypothesis that these
interesting 'Mars balls' are actually sedimentary concretions,
rather than any of the other working hypotheses," said James
Garvin, lead scientist for Mars Exploration and the Moon at NASA
Headquarters in Washington, D.C.
There have been a variety of contending theories for what may
have caused the unusual mineralogy at Meridiani, including
volcanic causes.
Garvin said that this latest finding strongly supports the view
that the rocks in the outcrop at Meridiani have been modified by
water - a determination made already through other research at
the site.
"Hematite as a major compositional phase in the spherules
supports their formation via precipitation, rather than as
impact-related fallout," Garvin said.
"So, the story is getting better... and multiple lines of
independent evidence support water-related chemical 'processing'
of the rocks," Garvin added. "Now all we have to do is figure
out what made the rocks in the first place and how long the
water may have been involved in the 'soakings.' What a fun
time!"
Copyright 1999-2004 SPACE.com, Inc.
[UFO UpDates thanks Norman for the lead]